Perpetual calendar



H. W. MAY

PERPETUAL CALENDAR Filed Feb.

1924 2 Sheets-Sheet 1 r 0 10 n e m I Horace WMay Jan. 5- 1,521,899

H. w. MAY

PERPETUAL CALENDAR Filed 1924 2 Sheets-Sheet 2 3&5. #19. 6.

Pnesem' FUTURE Inventor Horace (May Patented Jan. 6, 1925.

UNITED STATES HORACE W4 MAY, OF GARDENA, CALIFORNIA.

PERPETUAL CALENDAR.

Application filed February 25, 1924. Serial No. 694,925.

To all whom it may concern:

Be it known that I, HORACE W. MAY, a citizen of the United States, residing at Gardena, in the county of Los Angeles and State of California, have invented new and useful Improvements in Perpetual Calendars, of which the following isa specification.

My invention relates to calendars, and particularly to what is known in the art as perpetual calendars and the general object of my invention-is to provlde a perp etual calendar which is simple, inexpenslve and may be easily manipulated to find the calendar for any month of any year, past, present or future.

Other objects and advantages will appear hereinafter, and while I show herewith and will describe a preferred form of construction, I desire to be understood that I do not limit myself to such preferred form, but that various changes and adaptions may be made therein without departing from the spirit of my invention as hereinafter claimed.

My invention is illustrated in the annexed drawing, which forms a part of this specification, in which Fig. 1 is a face view of the stationary dial of my calendar.

Fig. 2 is a transverse section of said dial taken on line 22 of Fig. 1.

Fig. 3 is a front face view of the rotatable dial.

Fig. 4 is a transverse section of said rotatable dial taken on line 4-4 of Fig. 3.

Fig. 5 is a face view of my calendar.

Fig. 6 is a transverse section of my calendar taken on line 6 6 of Fig. 5.

Fig. 7 is a rear face view of the rotatable dial.

My calendar includes two dials 1 and 2, made of any suitable material, such as cardboard, and pivoted together centrally with the dial 1 upon the dial 2 by an eyelet 3 extending through said dials and flanged over their outer faces. The dial 1 is provided with an opening 4 above but near its center, the lower and upper edges of which opening being arcuate, struck from the center of the dial, and the end edges of said 0 ening extending radially from the center of the disk.

The dial 1 is also provided with a slot 5 below and away from its center, the side edges of which slot extend radially from the center of the dial, and the upper and lower edges of said slot being arcuate, with the lower edge near the periphery of the dial'and the upper edge coinciding with a circle of which the lower edge of the opening 4 forms an arc. I

On the dial 1 along the upper edge of the opening 4, from left to right, are indicated the days of the week, as follows: Sun.,.Mon., Tues, 'VVed, Thu, Fri., Sat.

On said dial along the left edge of the slot 5 from top to bottom are indicated the months of the year as follows: J an., Feb., Feb., Mar., Apr., May, June, July, Aug, Sept.,Oct.,Nov.,Dec., the month of February being indicated twice, and on the dial along the right edge of said slot, from top to bottom, opposite said month indications-respectively, are indicated the number of days of said months respectively as follows: 31, 28, 29, 31, 30, 31, 30, 31, 30, 31, 30, 31, the twenty-nine days opposite the lower month of February indicating leap years.

On the inner face of the dial 2 are three circles, a small inner circle 6, a larger or intermediate circle 7 and an outer circle 8, the space between the inner and intermediate circles coinciding with the opening 4, and the space between the intermediate and outer circles coinciding with the slot 5. Said face of said dial is divided by twentyeight radial lines 9, spaced equi-dista-nt apart, and extending from said inner circle 6 to said outer circle 8, into spaces 10 between the circles 6 and 7 and into spaces 11 between the intermediate circle 7 and the outer circle 8.

In the spaces 10 from left to right are indicated four spiral rows of numbers each from 1 to 31, said rows each extending from the intermediate circle 7 to the inner circle 6, and the number 1 of each row being located in the seventh space 11 from the spaces in which the numbers 1 of the nearest other rows are located. In the spaces 11 are indicated the years from 1920 to 1944 so that they will register with said month indicat-ions at the left of the slot 5 when the spaces respectively register with said slot, the years being so arranged in said spaces that when a given year is opposite a given month, certain numbers in the spaces 10 will register with the days of the week at the upper edge of opening 4 to give the calendar for said month of said year as indicated in Fig. 5.

The numbers at the right edge of the slot 5 indicate how many days to read in a month as it appears in opening 4. On the rear face of the dial 2 is indicia to be read in conjunction with the face of the calendar for determining the calendar of past years as far back as the year 1855, and of future years as far ahead as the year 2000.

In the center of the rear face of the dial is a vertical column 15 in which are indicated from top to bottom the years 1923 to 1940. To the left of said column opposite said year indications are indicated the last two digits of the past years from 1855 up to 1920 except the year 1900. the number 18 being indicated before the digits of the 19th century, and the year 1900 being indicated before the last two digits of the following years of the 20th century.

To the right of the column 15, opposite the year indications in said column, are indicated the last two digits of the future years from 1941 up to 1999 and also the four digits of the future year 2000,

A comparison of the calendars of a. series of successive years will show that there is a periodic recurrence of years in which the days of the month and the days of the week coincide throughout the year. The table containing the indicia referred to is arranged in accordance with this fact.

As is indicated therein, the years 1855, 66, 77, 83, 94, 1900, 06, 17 coincided in this respect with the year 1923, as will the years 1945, 51, 62, 73, "79 and 1990. Likewise the years 1856, 84 coincided with the year 1924, as will the years 1952 and 1980 and so on throughout the table.

The use of the table in finding dates which do not appear on the face of the calendar is therefore evident. For example: To find the month of August, 1855, reference is made to the table which shows that the year 1855 coincided with the year 1923. Dial 2 is then turned with reference to dial 1 until the year 1923 on the face of dial 2, seen through slot 5, coincides with the month August on the face of dial 1, as is shown in Fig. 5. The days of the month and cor- Y back and ahead indefinitely.

I claim as my invention:

1. A per etual calendar comprising two dials turna ly connected together, the front dial having, an opening and. a slot. the days of the week being indicated at one edge of said opening, the months of the year being indicated at one edge of said slot, the years being indicated on the rear dial in position to coincide with said slot and to register with said month indications, and the nu1nbers of the days: of the week being indicated on said rear dial in position to coincide with said opening and to register with said week day indications to give the calendar of a month of a year which registers with said month as indicated at said edge of said slot.

2. A perpetual calendar comprising two dials turnably connected together, the front dial having, an opening and a slot, the days of the week being indicated at one edge of said opening, the months of the year being indicated at one edge of said slot, the years being indicated on the rear dial in position to coincide with said slot and to register with said month indications, and the numbers of the days of the. week being indicated on said rear dial in position to coincide with said opening and to register with said week day indications to give the calendar of a month of a. yearwhich registers with said month as indicated at said edge of said slot, said week day numbers being arranged in spiral rows from 1 to 31 so that the numbers of one roW come under the numbers of another row in the order of the numbers of the days of the month.

3. A perpetual calendar comprising two dials turnably connected together, the front dial having, an opening and a slot, the days of the week being indicated at one edge of said opening, the months of the year being indicated at one edge of said slot, the years being indicated on the rear dial in position to coincide with said slot and to register with said month indications, and the numbers of the days of the week being indicated on said rear dial in position to coincide with said opening and to register with said week day indications to give the calendar of a month of a year which registers with said month as indicated at said edge of said slot, the number of days of each month being indicated on said front dial opposite said month indications.

4. A perpetual calendar comprising two dials turnably connected together, the front dial having, an opening and a slot, the days of the week being indicated at one edge of said opening, the months of the year being indicated at one edge of said slot, the years being indicated on the rear dial in position to coincide with said slot and to register with said month indications, and the numbers of the days of the week being indicated on said rear dial in position to coincide with said opening and to register with said week day indications to give the calendar of a month of a year which registers with said month as indicated at said edge of said slot, the number of days of each month being indicated on said front dial opposite said month indications and the month of February being indicated twice on said dial and the number 29 being indicated on said dial after one of said February indications for determining the calendar of the month of February in leap years.

5- A perpetual calendar comprising two dials turnably connected together, the front dial having, an opening and a slot, the days of the week being indicated at one edge of said opening, the months of the year being indicated at one edge of said slot, the years being indicated on the rear dial in position to coincide with said slot and to register with said month indications, and the numbers of the days of the week being indicated on said rear dial in position to coincide with said opening and to register with said week vday indications to give the calendar of a month of a year which registers with said month as indicated at said edge of said slot, there being indicia on the back of said rear dial to be read in conjunction with the front face of said dial and the front face of said front dial to give the calendar for years past and future which are not given by the front faces of said dials.

6. A perpetual calendar comprising two dials turnably connected together, the front dial having, an opening and a slot, the days of the week being indicated at 0116 edge of said opening, the months of the year being indicated at one edge of said slot, the years being indicated on the rear dial in position to coincide with said slot and to register with said month indications, and the numbers of the days of the week being indicated on said rear dial in position to coincide with said opening and to register with said Week day indications to give the calendar of a month of a year which registers with said month as indicated at said edge of said slot, there being indicia on the back of said rear dial including a column in which are indicated certain of the years which are indicated on the front face of said dial, past years at one side of said column and opposite said column years, and future years at the other side of said column and opposite said column years, said indicia being so ar ranged that the calendar of any month of any past or future year on the back of said dial may be caused to appear in said opening in said front dial when the year in said column, opposite said past or present year, on the front of said rear card, is brought into said slot opposite the same month on said front dial. v

HORACE W. MAY. 

